12-102852829-C-T

Variant names:

• chr12-102852829-C-T
• rs62514954
• NM_000277.3:c.828G>A

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_000277.3(PAH):​c.828G>A​(p.Met276Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,150 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M276R) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: PAH NM_000277.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 2.62
• Publications: 3 publications found

Genes affected

PAH (HGNC:8582): (phenylalanine hydroxylase) This gene encodes a member of the biopterin-dependent aromatic amino acid hydroxylase protein family. The encoded phenylalanine hydroxylase enzyme hydroxylates phenylalanine to tyrosine and is the rate-limiting step in phenylalanine catabolism. Deficiency of this enzyme activity results in the autosomal recessive disorder phenylketonuria. [provided by RefSeq, Aug 2017]

PAH Gene-Disease associations (from GenCC):

• phenylketonuria

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, ClinGen, Myriad Women’s Health
• classic phenylketonuria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• maternal phenylketonuria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• mild hyperphenylalaninemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• mild phenylketonuria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• tetrahydrobiopterin-responsive hyperphenylalaninemia/phenylketonuria

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 13 ACMG points.

• PM1: In a hotspot region, there are 40 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 5 uncertain in NM_000277.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr12-102852830-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 102858.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 440 curated pathogenic missense variants (we use a threshold of 10). The gene has 8 curated benign missense variants. Gene score misZ: -0.64755 (below the threshold of 3.09). Trascript score misZ: -0.0084567 (below the threshold of 3.09). GenCC associations: The gene is linked to phenylketonuria, tetrahydrobiopterin-responsive hyperphenylalaninemia/phenylketonuria, maternal phenylketonuria, classic phenylketonuria, mild phenylketonuria, mild hyperphenylalaninemia.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.963
• PP5: Variant 12-102852829-C-T is Pathogenic according to our data. Variant chr12-102852829-C-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 551519.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PAH	NM_000277.3	c.828G>A	p.Met276Ile	missense_variant	Exon 7 of 13	ENST00000553106.6	NP_000268.1
PAH	NM_001354304.2	c.828G>A	p.Met276Ile	missense_variant	Exon 8 of 14		NP_001341233.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PAH	ENST00000553106.6	c.828G>A	p.Met276Ile	missense_variant	Exon 7 of 13	1	NM_000277.3	ENSP00000448059.1
PAH	ENST00000307000.7	c.813G>A	p.Met271Ile	missense_variant	Exon 8 of 14	5		ENSP00000303500.2
PAH	ENST00000549247.6	n.587G>A		non_coding_transcript_exon_variant	Exon 1 of 6	2
PAH	ENST00000635477.1	c.-13G>A		upstream_gene_variant		5		ENSP00000489230.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152150 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 31

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152150 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74332

African (AFR) AF: 0.00 AC: 0 AN: 41424

American (AMR) AF: 0.00 AC: 0 AN: 15256

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68044

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.0000712 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Phenylketonuria Pathogenic:1 Uncertain:1

Apr 14, 2017

Counsyl

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Jun 22, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 551519). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt PAH protein function. This variant disrupts the p.Met276 amino acid residue in PAH. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 8068076, 16256386, 16290003, 25894915, 29176022, 30459323, 30612563). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. This missense change has been observed in individual(s) with a positive newborn screening result for PAH-related disease (Invitae). This sequence change replaces methionine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 276 of the PAH protein (p.Met276Ile). This variant is present in population databases (no rsID available, gnomAD 0.007%). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.70
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.83	D;D
Eigen	Benign	0.19
Eigen_PC	Uncertain	0.28
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.96	D;D
M_CAP	Pathogenic	0.56	D
MetaRNN	Pathogenic	0.96	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.9	M;.
PhyloP100		2.6
PrimateAI	Uncertain	0.62	T
PROVEAN	Benign	-1.4	N;N
REVEL	Pathogenic	0.69
Sift	Uncertain	0.013	D;D
Sift4G	Uncertain	0.033	D;D
Polyphen		0.14	B;.
Vest4		0.70
MutPred		0.89		Loss of solvent accessibility (P = 0.0387);.;
MVP		0.96
MPC		0.042
ClinPred		0.84	D
GERP RS		5.7
PromoterAI		-0.050	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.81
gMVP		0.91
Mutation Taster		=20/80	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs62514954; hg19: chr12-103246607;